Hi
Please be aware that in the Beta Channel, features may come and go. Microsoft hopes you will send feedback on the features as they are developed. Tell them what you like, tell them what could be better, tell them when something doesn't work and then again when it does work, give Microsoft suggestions using the Help menu's Feedback option.
Beta Channel updates are weekly, and can be very large downloads, so if you have a limited data plan, that might be a problem.
Questions and comments about beta channel builds should be made in the Office Insider forum of the Community instead of this forum.
MOST of the time beta channel builds are stable, but they are beta and you are testing things that have not yet been tested, so you might discover a crash or something really weird on occasion. But that's part of the fun!
Here's more information on the program